Transportation Engineering Civil Engineering Department 4 th Stage

Transportation Engineering Civil Engineering Department 4 th Stage, 1 st Semester, 2019 -2020 15 th Lecture: Intersections Lecturer Dr Maha Osamah 1 Dr Abeer K. Jameel

Intersections �Intersection is an area shared by two or more roads which meet or cross. �It is designated for vehicles to turn to different direction �Turning need specific space for vehicles �At grade and interchanges 2

Intersection Types �At grade Intersections �Grade separated Intersection (interchanges) 3

Intersection Types At grade Intersections may be classified by number of road segments, traffic controls or lane design. � By road segment : three-leg, four-leg , and multi-leg � By traffic control: uncontrolled, priority, stop-controlled, yield controlled, signalised intersection…… 4

At Grade Intersections three- leg intersection 5 T – intersection

At Grade Intersections three- leg intersection 6 Y – intersection

At Grade Intersections Four- leg intersection 7

At Grade Intersections four- leg intersection 8

At Grade Intersections Roundabout 9

At Grade Intersections Warrants: • Traffic volume and conflicts • Land availability • Economy 10

At Grade Intersections Traffic conflicts Both direction One way 6 conflict points 11

At Grade Intersections Traffic conflicts Both direction Two way 24 conflict points 12

At Grade Intersections 13

At Grade Intersections 14

At Grade Intersections 15

At Grade Intersections 16

At Grade Intersections 17

At Grade Intersections 18

At Grade Intersections 19

At Grade Intersections 20

Grade separated and Interchanges • Elimination of crossing conflicts at intersection by vertical separation of roadways • Route transfer at grade separation is accommodated by interchanges consisting of ramps 21

Grade separated and Interchanges Grade separated 22

Grade separated and Interchanges Grade separated , Underpass 23

Grade separated and Interchanges Grade separated , Overpass 24

Grade separated and Interchanges 25

Grade separated and Interchanges 26

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